Electric relay



L. H. PETER-ET AL 'ELECTRIC RELAY June 9, 1936.

Filed Oct. 14, 1953 3 Sheets-Sheet 1 IN VENTORS Hurst Peter andfiMarvw/ffaodmgor THEIR ATTORNEY ELECTRIC RELAY Filed Oct. 14, 1933 5Sheets-Sheet 2 INVENTORS Leskl/urszPeier and THEIR A TTORNE Y PatentedJune 9, 1936 UNITED STATES PATENT OFFICE ELECTRIC RELAY ApplicationOctober 14, 1933, Serial No. 693,614

In Great Britain October 20, 1932 7 Claims.

This invention relates to electric relays of the time element type inwhich the relay contacts are adapted to be opened or closed only afterthe expiration of a predetermined interval of time from the energizationor denergization of the relay.

The invention has for its object to provide an improved relay of thischaracter and according to the principal feature of the invention therelay comprises an electrically operated motor mechanism which isarranged to be started into operation when the relay is energized ordeenergized and to be operatively coupled by an electrically actuatedclutch me'chanismor its equivalent to a rotary mechanism adapted toeffect the operation of the relay contacts after this mechanism has beenrotated to a predetermined extent by the motor mechanism.

The invention is illustrated by way of example in the accompanyingdrawings of which Figures 1 and 2 are views in front elevation and planrespectively of a time element relay adapted to be operated by directcurrent and constructed in accordance with a preferred form of theinvention. Figure 3 is a view of the relay in side elevation and Figure4 a detail view on an enlarged scale of a portion of the relaymechanism. Figure 5 is a diagrammatic view of the circuit connections ofthe relay shown in the preceding figures. Figure 6 is a plan viewsimilar to Figure 2 of a modified construction of relay adapted to beoperated by alternating current, Figure '7 being a view similar toFigure 5 showing the circuit connections of the relay of Figure 6.

Referring now first to the relay shown in Figures 1 to 5 inclusive, itwill be seen that the relay comprises arocking member I carrying movablecontacts 2 adapted to cooperate with fixed contacts 3 of the relay tocontrol the relay circuits in theusual manner. The rocking member I ismounted in trunnion bearings 4 and is connected by means of a link 5 toone end of an arm 6 the opposite end of which is connected to the Vpivotally mounted armature l of an operating electromagnet 8 providedwith an energizing coil 9.

The energizing circuit of the coil 9 includes a contact Ill (see Figure5) controlled by the rocking member I, this contact being open when therelay is deenergized, a branch circuit for energizing the coil 9including a spring contact I l and a contact [2 carried on a springcontact arm l3. The contact arm l3 also carries an operating member l4adapted to engage with the periphery of a cam disc l5 provided with acam projection l6.

The relay also comprises motor mechanism comprising a toothed wheel I!adapted to be rotated step by step by means of a pawl l8 carried by themovable armature IQ of an electromagnet having an energizing coil 20. Asshown in Figure 5, the armature l9 also controls contacts 2| included inthe energizing circuit of the coil 20, a rectifier 22 being connectedacross the terminals of the coil 20 for the purpose of providing a freepath for the reverse current when the contacts 2! are opened.

The operation of the motor mechanism above described will be understoodwithout further explanation and it will be seen from Figure 5 that withthe rocking member I of the relay in its deenergized position a circuitis completed from the terminal 23 through wires 24 and 25, the coil 29of the motor mechanism, contacts 2|, wires 26 and 21, contacts 28,closed when the rocking member is in the position shown, and wire 29 tothe other relay terminal 30.

It will thus be evident that when energizing current is supplied to theterminals 23, 30 of the relay, the wheel I! will be rotated step by stepby means of the pawl l8 so long as the rocking member I remains in theposition shown in Figure 5.

The shaft 3| of the motor mechanism on which the toothed wheel I1 ismounted is provided with a pinion 32 with which an idler pinion 33 isadapted to intermesh when moved into engagement therewith by means of aclutch magnet 34 comprising a coil 35 and a movable armature 36connected by arms 3! to the idler pinion 33. The pinion 33 intermesheswith a gear wheel 38 mounted on a shaft 39 carrying the cam disc IS, theshaft 39 being provided with a pinion 40 intermeshing with a toothedsegment 4| carrying a counterweighted arm 42 for restoring the shaft 39and cam disc l5 to its normal position when the motor device and clutchare deenergized.

The coil 35 of the clutch magnet 34 is connected across the wires 25, 21as shown in Figure 5 so that operating current is supplied to the coil35 when the relay is energized and so long as the contacts 28 areclosed.

Projecting from one face of the cam disc I5 is a stop 43 adapted toengage with a stop 44 projecting from the adjacent face of a gear wheel45 loosely mounted upon the shaft 39, the gear wheel 45 engaging with aworm 46 carried on the lower end of a rotatable vertical spindle 41, theupper end of which projects through the top plate 48 of the relay asshown in Figure 3. By rotating the spindle 41 the angular position ofthe gear wheel 45 and of the stop 44 carried thereby can be adjusted asdesired, this position being indicated by a pointer 49 adapted to moveover a scale (not shown) graduated in minutes or seeonds.

The operation of the relay is as follows:

Under normal or release conditions in which the relay is not beingsupplied with energizing current, the rocking member I is in itsinoperative position shown in Figure 5 so that a circuit for the motordevice is completed from the terminal 23 to the terminal 39 as abovedescribed while a circuit for the coil 35 of the clutch magnet 34 isalso completed from terminal 23 through wires 24, 25 and 49, the coil 35and wire 21 to the terminal 39. The clutch magnet 34 being deenergizedthe idler pinion 33 is out of engagement with the motor pinion 32 andthe shaft 39 carrying the gear wheel 39 and cam disc I5 is maintained bythe counterweighted arm 42 in an angular position determined by theposition to which the stop 44 has been adjusted by the spindle 41. Theprojection 16 on the cam disc 15 will thus be separated from theoperating member l4 by a predetermined angular distance and the contactl2 being out of engagement with the contact H the circuit of the coil 9of the operating magnet 8 is interrupted.

When energizing current is supplied to the relay the motor mechanismcommences to rotate and the coil 35 of the clutch magnet 34 beingenergized the idler pinion 33 is moved into engagement with the pinion32 so that the rotation of the ratchet wheel I! is transmitted to thegear wheel 38 and to the cam disc [5 which are thereby rotated raisingthe counterweighted arm 42.

As soon as the cam disc l5 has been rotated to an angular extentsufiicient to bring the pro jection l6 into engagement with theoperating member l4, the contact I2 is caused to engage with the contactll thus completing the energizing circuit of the operating magnet 8 fromterminal 23 through wires 24 and 59, the coil 9 of the magnet 8, wire5|, contacts II and I2 and wire 52 to the terminal 39. The armature l ofthe operating magnet 8 is thus attracted and operates the rocking memberI to its energized position in which the relay contacts are operated andthe contacts l9 are closed and the contacts 28 opened.

The closure of the contacts l9 completes a stick circuit for the coil 9of the operating magnet 8 from terminal 23 through wires 24, 59, coil 9,wire 5|, contacts [9 and wire 29 to terminal 39 so that the coil 9remains energized so long as energizing current is supplied to the relayterminals 23, 30.

The opening of the contacts 28 interrupts the circuits for the coil 35of the clutch magnet 34 and for the coil 29 of the motor mechanism sothat the latter ceases to operate and the armature 36 of the clutchmagnet 34 is released thereby causing the idler pinion 33 to bedisengaged from the pinion 32.

The gear wheel 38 and cam disc 15 are then free to be returned to theirnormal positions under the action of the counterweighted arm 42, whilethe rocking member I is maintained in its energized position so long asenergizing current continues to be supplied to the relay.

When the supply of energizing current to the relay is interrupted, thecoil 9 of the operating magnet 8 is deenergized and the rocking memberreturns to its inoperative position.

It will be understood that the extent to which the cam disc [5 must berotated from its normal position so as to permit the projection It toengage with the operating member M will be dependent upon the originalposition of the cam disc 15 as defined by means of the stop 44 which bymeans of the gear Wheel 45, worm 49 and adjusting spindle 41 is arrangedto be adjusted so as correspondingly to vary the interval of timerequired to bring the cam projection It to a position to operate themember M as above explained.

Referring now to the modified constructions shown in Figures 6 and 7 itwill be seen that the motor mechanism of the relay consists of a smallsynchronous motor 62, one terminal 53 of which is connected to the wire26 leading through the contacts 28 and the wire 29 to terminal 39 of therelay, the other terminal 54 of the motor 62 being connected through awire 55, to the wire 25 leading to the other terminal 23 of the relay.

A rectifier 56 is connected across the terminals of the coil 35 of theclutch magnet 34 so as to enable the latter to be operated by rectifiedcurrent and a high resistance 51 is, connected between the terminal 53of the motor 52 and the rectifier 59 as shown in Figure 7.

The operation of this form of relay is substantially the same as that ofthe construction previously described With reference to Figures 1 to 5inclusive and will be readily understood without further explanation.

The invention is evidently not limited to the particular construction orarrangements above described and illustrated by way of example which maybe modified in various respects without exceeding the scope of theinvention.

Having now particularly described and ascertained the nature of our saidinvention and in what manner the same is to be performed, We declarethat what we claim is:

1. A normally energized electric relay comprising, in combination, anormally deenergized electrically operated motor mechanism, means for attimes energizing said motor mechanism to cause operation thereof, arotary mechanism, means effective when said motor mechanism is energizedfor coupling said motor mechanism to said rotary mechanism, and meanscontrolled by said rotary mechanism for effecting the operation of thecontacts of said relay after said rotary mechanism has been rotated to apredetermined extent by said motor mechanism and for deenergizing saidmotor mechanism.

2. An electric relay comprising, in combination, a normally deenergizedelectrically operated motor mechanism, means for at times energizingsaid motor mechanism to cause operation thereof, a rotary mechanism,means eifective when said motor mechanism is energized for coupling saidmotor mechanism to said rotary mechanism, an operating electromagnet, agoverning contact controlled by said rotary mechanism in such manner asto become operated when said rotary mechanism has been rotated to apredetermined extent by said motor mechanism, an energizing circuit forsaid electromagnet controlled by said governing contact, a secondcontact controlled by said electromagnet and a holding ciredit for saidelectromagnet including said second contact.

3. An electric relay comprising, in combination, a normally deenergizedelectrically operated 75 motor mechanism, means for at times energizingsaid motor mechanism to cause operation thereof, a rotary mechanism,means effective when said motor mechanism is energized for coupling saidmotor mechanism to said rotary mechanism, an operating electromagnet, acontact controlled by said rotary mechanism in such manner as to becomeoperated after the expiration of a predetermined interval of time fromthe energization of said motor mechanism, a circuit for saidelectromagnet controlled by said contact, and means controlled by saidelectromagnet for deenergizing said motor mechanism.

4. An electric relay comprising, in combina tion, a normally deenergizedelectrically operated motor mechanism, means for at times energizingsaid motor mechanism to cause operation thereof, a rotary mechanismhaving a normal position of rest, means effective when said motormechanism is energized for coupling said motor mecha nism to said rotarymechanism, an operating electromagnet, a governing contact controlled bysaid rotary mechanism in such manner as to become operated when saidrotary mechanism has been rotated to a predetermined extent from saidnormal position of rest by said motor mechanism, a circuit for saidelectr-omagnet controlled by said governing contact, means controlled bysaid electromagnet for deenergizing said motor mechanism, and means foradjustably changing the normal position of rest of said rotary mechanismto vary the extent to which said rotary mechanism must be rotated beforesaid governing contact becomes operated.

5. A normally energized electric relay comprising, in combination, anormally deenergized electrically operated motor mechanism, means forenergizing said motor mechanism to cause operation thereof, a rotarymechanism, a clutch mechanism including a clutch magnet and an idlerpinion, means effective when said motor mechanism is energized forcoupling said motor mechanism to said rotary mechanism by means of saidclutch magnet and said idler pinion, and means controlled by said rotarymechanism for effecting the operation of the contacts of said relayafter said rotary mechanism has been rotated to a pre determined extentby said motor mechanism and for deenergizing said motor mechanism.

6. An electric relay comprising, in combination, a normally deenergizedelectrically operated motor mechanism, means for at times energizingsaid motor mechanism to cause operation thereof, a rotary mechanismcomprising a ratchet wheel which is rotated step by step by means of anelectro-magnetically operated pawl, means efiective when said motormechanism is energized for coupling said motor mechanism to said rotarymechanism, and means controlled by said rotary mechanism for effectingthe operation of the contacts of said relay after said rotary mechanismhas been rotated to a predetermined extent by said motor mechanism andfor deenergizing said motor mechanism.

7. An electric relay comprising, in combination, a normally deenergizedelectrically operated motor mechanism comprising a synchronousalternating current motor, means for at times energizing said motormechanism to cause operation thereof, a rotary mechanism, means effective when said motor mechanism is energized for coupling said motormechanism to said rotary mechanism, and means controlled by said ro- 1tary mechanism for effecting the operation of the contacts of said relayafter said rotary mechanism has been rotated to a predetermined extentby said motor mechanism and for deenergizing said motor mechanism.

LESLIE HURST PETER.

RODERICK MARCUS MAcGREGOR.

